Valve arrangement for diving equipment

ABSTRACT

The invention relates to a valve for diving equipment which comprises a valve housing having a charging port, a bottle port and an outlet port. Reducing valve means and reserve valve means are provided in series in the main fluid flow path. The reserve valve means remains open until a pressure on the downstream side thereof has dropped to a point where air in the bottle is at a predetermined low pressure, at which time the reserve valve closes. The reserve valve has means associated therewith which are manually operable to open the reserve valve to allow the remaining contents of the bottle to be fully utilized.

United States Patent 1 Lens [ VALVE ARRANGEMENT FOR DIVING EQUIPMENT[75] Inventor: Hans Otto Lerris, Nordborg,

Denmark [73] Assignee: Danfoss AIS, Nordborg, Denmark [22] Filed: Mar.25, 1971 [21] Appl. No.: 128,048

[30] Foreign Application Priority Data Apr. 16, 1970 Germany P 20 18146.8

[52] U.S. Cl. 137/612.1 [51] Int. Cl. Fl6k 17/04 [58] Field of Searchl37/6l2.1, 63 R, 137/608, 568

[56] References Cited UNITED STATES PATENTS 3,534,771 10/1970 Eyerdam137/525 X 3,561,477 2/1971 Pinto t l37/614.l9 3,207,179 9/1965 Klagues137/612.1 2,806,479 9/1957 Bennett... 137/63 R 3,037,502 6/ 1962 Gibbenset al. 137/63 R 11/1963 Galeazzi 137/63 R [451 July 10,1973

3,244,196 4/1966 Replogle 137/63 R 3,351,089 11/1967 Garrahan 137/63 R3,426,790 2/1969 D ..-137/63 R 3,477,463 11/1969 Worden 137/6l2.1 X

FOREIGN PATENTS OR APPLICATIONS 1,148,040 5/1963 Germany 137/63 R1,150,874 6/1963 Germany 137/63 R Primary Examiner-Samuel ScottAttorneyWayne B. Easton [5 7] ABSTRACT the reserve valve to allow theremaining contents of the bottle to be fully utilized.

. 1 Claim, 5 Drawing Figures PATENTELJUL 1 012m sum 1 OF 2 VALVEARRANGEMENT FOR DIVING EQUIPMENT The invention relates to a valvearrangement for diving equipment, particularly for automatic breathingapparatus, and for connection to a compressed-gas contained having acut-off valve and a reserve switch, which blocks the gas outlet when thepressure drops below a predetermined minimum and then has to be manuallyoperated to draw off further gas.

Pressurized containers (called bottles) are used for supplying oxygen toa diver and these are filled with oxygen or air under a high pressure offor example, 200 atmos. This pressure falls as the gas is used up. Acutoff valve is fitted on the pressurized container and closes thebottle when the latter is not in use. Adjoining this valve is a reserveswitch. This responds when the pressure in the bottle falls below apredetermined minimum of 30 atmos. for example, and closes the gasoutlet with the help of a closure member. This is the signal for thediver to start to surface. By switching over with the help of afluid-tight outwardly extending actuating member, he can open a by-passwhich short-circuits the above-mentioned closure member, and he can thususe up the remaining contents of the bottle. The actual breathingapparatus is connected to the output side of the cut-off valve andreserve switch associated with the bottle. This apparatus usuallyconsists of a reduction stage which lowers the pressure'in the bottleto, for example, 4 atmos. above the pressure of the water, and of adispensing stage whic, by further reduction, lets out air at a pressurecorresponding to the depth of water.

The seal associated with the actuating member for the reserve switchmust be of very high quality so that it operates satisfactorily despitethe high pressures. Also, after the reserve switch has been reversed, alarge quantity of gas is still available, so that the diver may betempted not to surface immediately.

The object of the invention is to provide a valve arrangement of theinitially stated kind and whereby the difficulties associated with theknown reserve switch can be avoided.

This object is achieved by fitting a reducing valve between the cut-offvalve and the reserve switch.

This reducing valve reduces the pressure in the bottle to apredetermined pressure or pressure-range, e.g., to atmos. The reserveswitch is therefore subjected to a considerably lower pressure thanpreviously. With this arrangement,-the lead-through opening whereby the,operating element of the reserve switch is connected to the associatedhandle does not require to be nearly so tightly sealed, because of thelower pressure. Furthermore, the pressure at which the reserve switchresponds can be kept much lower, so that the quantity of reserve air isonly sufficient for surfacing, so that the diver is not tempted toremain submerged any longer. The reducing valve moreover is enabled todeal with input pressures of difi'erent levels so that it is immaterialwhether the connected pressure container has a pressure of 200 or 300atmos. when full.

The provision of the reducing valve between the cutoff valve and thereserve switch causes no or hardly any increase in the cost ofconstructing the arrangement as a whole, since it suffices if theconnected breathing apparatus has only one reducing stage correspondingto the dispensing stage previously employed. Alternatively, if tworeducing stages are in fact used, the first stage can be considerablysimplified.

It is particularly advantageous if the reserve switch and the reducingvalve are brought together to form one component. In this way, it is notpossible for mistakes to be made in the switching operation.Furthermore, the cost of the construction and of its assembly isreduced.

It is also expedient for the reducing valve and cut-off valve to becombined to form one component. This ensures that only gas at lowpressure can be drawn from the bottle fitted with the cut-off valve.Thus, when the bottle is connected to another container for transferringthe contents or for drawing off gas from the two containers in parallel(and the connected container is intended for use at a lower pressurewhen full), there is no risk of explosion of said connected container asa result of excessive pressure-load.

Safety is further increased by also providing the component with afilling union incorporating a non-retum valve. This means that thebottle can only be filledif this component comprising the cut-off valveand reducing valve is fitted.

The construction is further simplified by the reserve switch beingconstituted by a valve which is located in the main flow-path, and whichcloses when the pressure falls below a certain minimum level and whichthen has to be opened manually. This reserve valve has only one closuremember which is firstly operated in dependence upon pressure and canthen be immobilized in an open position by hand.

It is very advantageous if the minimum pressure at which the reserveswitch closes rises as the water pres sure rises. In this. way, thequantity of reserve gas is rendered dependent upon the diving depth andtherefore upon the period required to surface.

In a preferred embodiment, the closure member of the reserve switch isbiased by a diaphragm which seals the low-pressure chamber behind thethrottle point and which, under the effect of the force from a biasingspring and water pressure, offers resistance to the pressure in thischamber. Since the reducing valve becomes non-effective as soon as thepressure in the bottle falls below the required value, behind thereducing valve, the pressure in the bottle acts directly on theactuating diaphragm over the range in which the reserve switch responds.Since the rear side of the diaphragm is acted upon'by the externalpressure, i.e., by the pressure of the water, the pressure at which thereserve switch responds increases with the depth of the water.Furthermore, the diaphragm provides an excellent seal for the chamber inthe reserve switch.

The closure member of the reserve switch can also be connected to theconstricting element of the reducing valve in such manner that thereserve switch closes when the reducing valve reaches a predeterminedposition at which the opening is at its widest. This means that a singlepressure-dependent control operation suffices for the reserve switch andthe reducing valve.

It is particularly advantageous if the reserve switch has a lockingdevice which is dependent upon the entry pressure and which enables thereserve switch to be immobilized in the reserve position only when thepressure falls below a predetermined release pressure. This ensures thatthe diver does not inadvertently bring the reserve switch prematurelyinto the reserve position.

The invention will now be described in more detail by reference toembodiments illustrated in the drawing, in which:

FIG. 1 is a schematic illustration of a control system for the valvearrangement according to the invention,

FIG. 2 is a section through a first embodiment of the valve arrangementof the invention, the direction of the passages being illustratedschematically,

FIG. 3 is a similar sectional illustration of another embodiment,

FIG. 4 shows a detail of the arrangement of FIG. 3, in the lockedposition, and

FIG. 5 illustrates the parts seen in FIG. 4, but in the releasedposition.

The valve arrangement of the invention is accommodated in a unit 1which, together with a union 2 can be mounted on a pressure bottle 3,and to the outlet port 4 of which can be connected diving equipment,e.g., breathing apparatus 5, while the bottle 3 can be filled withpressurized gas by way of the charging port 6 of the unit 1. The unit 1contains a cut-off valve 17, a reducing valve 8, a reserve switch orreserve valve 9 and a non-return valve 10. The non-return valve ensuresthat gas can be drawn from the bottle 3 only by way of the reducingvalve 8 and the reserve valve 9 which are arranged in series. Thebreathing apparatus has only one reducing stage 1 1. This is sufficientsince, because of the presence of the reducing valve 8, only arelatively low pressure can be accepted at the outlet port 4,irrespective of the pressure to which the container 3 is filled.

As far as possible, corresponding parts of the embodiments describedbelow are designated by the same reference numerals as used in FIG. 1.

The cut-off valve 7 is fitted with a knob 12 which presses a closuremember 14 against a valve seat 15 when the threaded spindle 13 istightened. The spindle extends through the usual gland 16.

The reducing valve 8 contains a high-pressure chamber 17 and alow-pressure chamber 18. Located in the high-pressure chamber is athrottle element 19 which cooperates with a seat 20. The throttleelement is biased by a spring 21, which is backed by a screw 22. Thelow-pressure chamber is closed by a diaphragm 23 which is peripherallyclamped with the help of an attachment 24 and which carries at itscentre an actuating member 25 which can act on the throttle member 19through a needle-like extension 26. The diaphragm is biased on the oneside by the pressure in the chamber 18 and on the other side by theforce from a spring 27 and the pressure in the chamber 28, whichcommunicates with the surrounding water through an opening 29.

The reserve valve has a seat 30 and a closure member 31 which is securedto a spindle 32 and is biased on the one side by a spring 33 and on theother by the pressure of the out-flowing gas. The spindle is guided inan O- ring 34 and carries a pin 35 which cooperates with an inclinedsurface 36 on a handle 37 in such manner that, when this handle ismoved, the closure member 31 is immobilized in an open position.

The way in which this valve arrangement functions will be readilyunderstood. After the cut-off valve 7 has been opened the gas flows intothe high-pressure chamber 17 under the pressure at which it is containedin the bottle. When the gas has been used up at the outlet port 4, thepressure in the low-pressure chamber 18 drops.

The spring 27 then pushes the pin 26 to the left, so that the throttlemember 19 is lifted from its seat 20 and gas, the pressure of which iscorrespondingly reduced, passes from the high-pressure chamber '17 intothe lowpressure chamber 18. This low pressure is capable of holding thereserve valve 9 open. When the pressure in the bottle drops, thereducing valve 8 continues to open until finally the throttling actionceases virtually completely. The pressure in the bottle then actsdirectly on the reserve valve 9. When this pressure drops below thepredetermined minimum value, the reserve valve closes. By displacing theinclined surface 36, the cut-off valve can be opened again andimmobilized in the open position. The remaining contents of the bottleare then still sufiicient to enable the diver to surface.

The construction shown in FIG. 3 is very similar so that like referencenumerals are used for similar parts.

In this arrangement, the reserve valve 9 is connected to the reducingvalve 8 through the needle-like extension 26. The actuating member 25carries a closure member 38 in the form of a sealing ring whichcooperates with a valve seat 39. When the throttle member 19 has reachedthe position in which the opening is at its widest, the closure member38 bears on the seat 39. The actuating member 25 is provided with aspindle 40 which projects from the attachment 24 and carries at its freeend a rotatable knob 41 and a pin 32. This pin is enabled to remain onthe inclined surface 43 of a cam element 44 when the knob 41 is rotated.During this rotation, the closure member 38 is lifted from the seat 39.When the pin 42 engages in a recess 45 in the inclined surface 43, thecut-off valve is immobilized in its open position.

FIGS. 4 and 5 show the normal operating position somewhat moreprecisely. In this operating position, the pin 42 is located at one ofthe ends of the cam surface; the spindle 40 has free axial play..If thepressure drops to such an extent that the cut-off valve 9 closes, thepin 42 moves from the position shown in FIG. 4 into the positionillustrated in FIG. 5. Then, by rotating the knob 41, the spindle 40 canbe lifted to anextent such that the cut-off valve is forced into theopen position. For locking purposes, a fixed stop 46 is provided on theattachment 24 and a movable stop 47 on the rotary knob 41. In the normaloperating position illustrated in FIG. 4, the two stops prevent the knob41 from being rotated. Only when the spindle has descended to theposition illustrated in FIG. 5 as a result of reduction of the pressurein the bottle is the lock released, so'that the knob 41 can be rotated.This ensures that, during normal operation, the reserve valve cannot beinadvertently actuated by rotation of the knob 41.

The arrangement shown in FIG. 3 also incorporates asafety valve 48 whichcomprises a valve seat 49, a diaphragm 50, an actuating member 51, aclosing spring 52 and a set-screw 53. If for some reason the pressure inthe outlet port 5 rises above the permissible level, the safety valve 48opens and discharges gas through the outlet 54.

I claim:

1. A valve for diving equipment comprising a housing having a chargingport and an outlet port, said housing also having a bottle port, fluidpath means between said charging port and said outlet port, a spur pathbetween said fluid. path means and said bottle port, cut-off valve meansbetween said spur path and said fluid path means, reducing valve meansin said fluid path means,

termined pressure at said outlet port, resilient means biasing saidreserve valve means towards a closed position and manual means formoving said reserve valve means to a fixed open position.

1. A valve for diving equipment comprising a housing having a chargingport and an outlet port, said housing also having a bottle port, fluidpath means between said charging port and said outlet port, a spur pathbetween said fluid path means and said bottle port, cut-off valve meansbetween said spur path and said fluid path means, reducing valve meansin said fluid path means, reserve valve means in said fluid path meansin series with and on the downstream side of said reducing valve means,said reserve valve means being biased towards an open position solely bypressurized fluid on the downstream side of said reducing valve meansand being automatically closeable in response to a predeterminedpressure at said outlet port, resilient means biasing said reserve valvemeans towards a closed position and manual means for moving said reservevalve means to a fixed open position.